The greenback dipped early in the European trading session, then edged higher as investors bet the new head of the US Federal Reserve would steer a steady course on monetary policy when he addresses lawmakers this week.

But came off its highs to be little changed toward the end of the US session.

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Westpac's Imre Speizer says while risk appetite had returned to US equities markets, but not to the US dollar.

"The USD index is unchanged on the day, after dipping during the European morning," he said in a Tuesday morning note.

"(While the) AUD made a round-trip from 0.7830 to 0.7893 and back."

Domestically, there are no major event risks for the local currency on Tuesday, with Mr Speizer expecting the Australian dollar to remain moving between 78 and 79 US cents.

The Aussie dollar is also lower against the euro but up slightly against the yen.